Open a belt-driven AHU casing after ten years: the black dust on the floor is your belt

Rétrofit EC-SWAP : avant (moteur et courroie) après (ventilateur EC roue libre)

Elastomer particles in the airflow and throughout the casing. Tension needs retightening, pulleys go out of alignment, vibration, bearings need maintenance.

On the energy side, the SuisseEnergie guide on replacing ventilation drives quantifies the losses: around 4% in belt transmission and 10% in the asynchronous motor, before the fan even starts moving air. In one documented case, switching to a high-efficiency motor delivered 42% savings at the same airflow rate.

Our answer: EC-SWAP.

A retrofit designed to integrate without touching the existing controls or electrical wiring: the motor-belt-fan assembly is replaced with a free-wheel EC fan, everything else stays as is.

Constant flow mode: nominal airflow is guaranteed regardless of filter clogging.
Constant pressure mode: the fan adjusts itself automatically to zone demand, ideal for VAV.
No more belt, no more particles, no more transmission maintenance.
Scalable retrofit, payback in 2 to 4 years.

Have a belt-driven AHU in your building stock? Let’s talk EC-SWAP.

Source: SuisseEnergie / SFOE, “Replacing the drive in ventilation systems,” 2018.